Cranial Cavity Flashcards
What lies in the hypophysial fossa?
Pituitary Gland
What two structures lie anterior and posterior to the pituitary gland?
anterior - Tuberculum sellae
posterior - dorsum sellae
What lies in the sella turcica?
Pituitary Gland
What layers would a needle penetrate if pressed into the scalp until it hit the parietal bone?
5 layers:
Skin -> dense CT -> aponeurotic layer -> Loose CT –> pericranium
What layer of the scalp does the occiptofrontalis muscle attach to?
Aponeurotic layer
What layer of the scalp contains the arteries, veins and nerves that supply the scalp?
Dense connective tissue layer
What meningeal layer contains the meningeal arteries that supply the meninges?
The periosteal layer of the dura mater.
What innervates the meninges?
Meningeal branches of the trigeminal nerve and 1st-3rd cervical nerves.
Which dural partition runs longitudinally and separates the two hemispheres?
Falx cerebri
Which dural partition runs horizontally and separates the cerebellum from the cerebral hemispheres?
tentorium cerebelli
Which dural partition covers the hypophysial fossa?
diaphram sellae
What structures pass through the foramina of the cribiform plate?
CN I (olfactory)
What structures pass through the optic canal?
CN II (optic) Opthalmic artery
What structures pass through the superior orbital fissure?
opthalmic veins CN III (oculomotor) CN IV (trochlear) CN V1 (opthalmic branch of trigeminal) CN VI (abducens)
What structures pass through the foramen rotundum?
CN V2 (maxillary branch of trigeminal)
What structures pass through the foramen ovale?
CN V3 (Mandibular brand of trigeminal) Accessory meningeal artery
What structures pass through the carotid canal
Internal carotid artery
Internal carotid nerve plexus (sympathetic)
What structures pass through the groove/hiatus of the facial canal?
greater petrosal n. (CN VII facial)
What structures pass through the internal auditory meatus?
internal auditory vessels CN VII (facial) CN VIII (vestibulocochlear)
What structures pass through the jugular foramen?
Internal jugular vein CN IX (glossopharyngeal) CN X (Vagus) CN XI (accessory)
What structures pass through the hypoglassal canal?
CN XII (hypoglossal) Emissary Vein
What structures pass through the foramen magnum?
vertebral arteries
CN XI (accessory)
Caudal brainstem/spinal cord
anterior and posterior spinal arteries
What structures pass through the Condyloid canal?
emissary vein
What are the veins that course through the spongy bone of the skull called?
diploic veins (they drain into the dural sinuses, just like the emissary veins)
What two layers separate to form the dural sinuses?
Inner meningeal layer and outer periosteal layer
Which dural sinus is blood from a diploic vein near the bregma likely to drain into?
bregma is the junction of the coronal suture and saggital suture. The superior sagittal sinus runs directly deep to it along the median of the skull.
What two dural partitions join to form the straight sinus?
Falx cerebri and tentorium cerebelli
Trace the most direct pathway of blood in the straight sinus out to through the internal jugular vein?
Straight sinus–>confluence of sinuses–>transverse sinus–>sigmoid sinus–>internal jugular vein (which passes through the jugular foramen)
Which sinus forms a loop around the pituitary gland?
intercavernous sinus
What are the two routes of blood flow leaving the cavernous sinus posteriorly?
superior petrosal sinus (which meets up with the transverse and sigmoid sinus)
inferior petrosal sinus (which dumps into internal jugular vein)
Which sinus lies along the inferior border of the falx cerebri?
inferior sagittal sinus
What does the inferior sagittal sinus drain into?
the straight sinus–>transverse sinus–>sigmoid–>internal jugular vein.
What is the middle meningeal artery a branch of?
Maxillary artery which is a branch of the external carotid a.
Cerebrospinal fluid is drawn from the spinal cord. The patient later reports headaches. What nerve is responsible for this pain sensation and what triggered it?
CS fluid is drained, the meninges in the brain ‘sag’ from lack of pressure and the branches of the trigeminal nerve signal pain
If someone receives a blow to the pterion, what artery would be in danger of being ruptured?
middle meningeal artery
How does CSF drain out of arachnoid space?
flows into arachnoid vili, which protrude into dural sinuses
Between which two layers will blood collect in an external hematoma?
skull and periosteal dura (even though periosteal dura is tightly bound to skull, it will push away)
Between which two layers will blood collect in an subdural hematoma?
dura and arachnoid (can occur without any sort of skull fracture)
Where will blood collect in an subarachnoid hematoma?
subarachnoid space
What structures lie on lateral wall of cavernous sinus?
CN III (oculomotor) CN IV (trochlear) CN V1 & V2 (trigeminal) CN VI (abducent)
What artery passes through the cavernous sinus?
internal carotid artery (enters then loops back so technically passes twice)
How do the vertebral arteries enter the skull?
the foramen magnum
How do the internal carotid arteries enter the skull?
right and left carotid canals.
How does the middle meningeal artery enter the skull?
foramen spinosum
How do sympathetic nerves enter the skull?
They follow the internal carotid a. through the carotid canal.
What two foramens does CN XI pass through?
Enters skull through foramen magnum, exits through the jugular foramen
